Вычислите 1) (5/6-3/7)*42 2)(14/15-3/5)*15 3)18*(8/9-5/18)

Question

Вычислите 1) (5/6-3/7)*42 2)(14/15-3/5)*15 3)18*(8/9-5/18)

Answer 1

1)(5/6-3/7)*42=17

1. 5/6-3/7=35-18/42=17/42

2. 17/42*42=17*42/42(сокращаем)=17

2)(14/15-3/5)*15=5

1. 14/15-3/5=14-9/15=5/15=1/3

2. 1/3*15=1*15/3(сокращаем)=5

3)18(8/9-5/18)=11

1. 8/9-5/18=16-5/18=11/18

2. 18*11/18=18*11/18(сокращаем)=11